Etiology

1
Etiology

• Genetic Component
• Family studies
• Monozygotic48
• Offspring of two parents with schizophrenia46
• Dizygotic17
• Sibling10-15
• (Gottesman, 1991)

2
Etiology

• Genetic influences
• Multiple genes?
• Quantitative trait loci
• Dean (November, 2002)
• 153 genes

3
Etiology

• Neurobiological Influences
• Dopamine
• Dopamine receptors
• D1 D4
• Observations supporting the role of dopamine
• Antipsychotic drugs (neuroleptics) are dopamine
  antagonists
• Neuroleptic side-effects resemble Parkinsons,
  which is associated with low dopamine levels
• Drug L-Dopa, a dopamine agonist used to treat
  Parkinsons has caused schizophrenic-like
  symptoms
• Amphetamines, which activates dopamine,
  aggravates psychotic symptoms in people

4
Etiology

• Neurobiological influences
• Observations that do NOT support role of Dopamine
• Many sz do not respond to neuroleptics
• Although neuroleptics block the receptor quickly,
  symptoms persist longer than one would expect
• Only partly effective for negative symptoms
• Conflicting evidence about whether people with sz
  have more D2 receptors than others
• clozapine

5
Etiology

• Brain Structure
• Ventricles
• Liquid-filled cavities are larger in some sz
• Specifically lateral ventricles
• More frequently observed among males
• Hypofrontality

6
Etiology

• Viral infection
• Prenatal exposure to influenza
• Can disrupt the developmental migration of
  neurons
• Fingertip dermal cells responsible for the number
  of fingerprint ridges
• Right hemisphere

7
Etiology

• Psychosocial influences
• Mednick Schulsinger (1968)
• Prospective study
• instability of early family rearing environment
• Stress and relapse
• Schizophrenogenic
• Double bind
• Expressed emotion
• Criticism
• Hostility
• Emotional overinvolvement

8
Treatment

• Biological
• Insulin coma therapy
• Psychosurgery
• Electroconvulsive therapy (ECT)

9
Treatment

• Neuroleptics
• 60 efficacy
• Extrapyramidal symptoms
• Motor difficulties
• Akinesia
• Expressionless, slow motor activity
• Tardive dyskinesia
• Involuntary movement of tongue, face, mouth, or
  jaw
• Protrusions of the tongue, puckering of the
  mouth, chewing movements
• Long-term use of neuroleptics is often
  irreversible

10
Treatment

• Psychosocial
• Token economy
• Adherence
• Suicide